public class Construct {
    public static void main(String[] args) {
        Son son1=new Son();
        System.out.println("***********************");
        Son son2=new Son("**==**");
    }
}

class Grandfather{
    public Grandfather(){
        System.out.println("This is Grandfather!");
    }
    public Grandfather(String s){
        System.out.println("This is Grandfather"+s);
    }
}

class Father extends Grandfather{
    public Father(){
        System.out.println("This is Father!");
    }
    public Father(String s){
        System.out.println("This is Father"+s);
    }
}

class Son extends Father{
    public Son(){
        System.out.println("This is Son!");
    }
    public Son(String s){
        System.out.println("This is Son"+s);
    }
}